“Truly, I say to you, all sins will be forgiven the children of man, and whatever blasphemies they utter, but whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin” (Mark 3:28-29, ESV).
Jesus states this theological conundrum in response to the scribes who were accusing Him of being possessed by an evil spirit. He replied that a kingdom can’t be divided against itself: “How can Satan cast out Satan?” (vs. 23). Then, Jesus seems to warn the scribes they may be the ones committing blasphemy!
Luke’s account complicates the conundrum. In Luke 12:10 Jesus says, “Anyone who speaks a word against the Son of Man will be forgiven, but the one who blasphemes against the Holy Spirit will not be forgiven.”
Today, we use these verses as the basis for the so-called doctrine of the unpardonable sin.
We generally consider blasphemy as contemptuous behavior towards God often exhibited by cursing or reviling God. But, there is an underlying theological supposition to blasphemy–that is, to attribute to oneself the rights or qualities of God.
The scribes’ indictment of blasphemy against Jesus in Mark 3 was based on that theological component. So, when Jesus answered them back, he used the scribes own faulty reasoning against them–their accusation of Jesus’ supposed blasphemy was in itself blasphemous!